//globals
co_radius=50;
co_height=30;

module complexObject() 
{

	difference() 
	{
     union()
     {
       cylinder(r=co_radius,h=co_height, center=true);
       for (r=[0:5])
       {
        	rotate([0,0,r*360/5]) 
			translate([co_radius,0,0]) 
			cube([10,10,co_height],center=true);
       }
     }
     union()
     {
     }
	} 
  
}

complexObject();